Influence of calcination treatment on the activity of tungstated zirconia catalysts towards esterification

In the present study, zirconia prepared by the solvothermal method was calcined under reductive (H2) and oxidative (O2) treatment to obtain ZrO2-H2 and ZrO2-O2, respectively. Then, they were impregnated with 15 wt% of tungsten (W) to produce W/ZrO2-H2 and W/ZrO2-O2 catalysts for esterification. It revealed that the presence of F-center was more dominant under the reductive treatment during calcinations of zirconia. Consequently, this can result in increased dispersion of tungsten indicating the existence of the surface monotungstates on the W/ZrO2-H2 catalyst. Therefore, the enhanced activity obtained from the W/ZrO2-H2 catalyst can be attributed to increased dispersion of tungsten and acidity.